You ordened a sidegrade.
So?
You entered your old (previous) Serial number AND you entered your new serial number corectly?

Just asking.

(and YES) attention to the blanks before and after the serial numbers.

If your serial number works on their test scenario, you should troubleshoot on your side.
Sorry , I feel your pain.

Poser 1, 2, 3, 4, 5, 7, P8 and PPro2010, P9 and PP2012, P10 and PP2014 Game Dev
"Do not drive faster then your angel can fly"!